1. Field of the Invention
This invention relates to a device for delivering fluids to the vascular system through the bone marrow cavity, a method of implanting such a device, and a method of using such a device. In particular, the device comprises an intramedullary catheter which is implanted in a bone and covered by the skin, providing access for the administration of fluids through the bone marrow into the vascular system.
2. Description of the Relevant Art
Intravenous devices are commonly used for the delivery of fluids, such as drugs or the like, directly to the vascular system. Most hospital patients are fitted with an intravenous device to provide the physician with easy access to the vascular system for the administration of such fluids. The advantages of intravenous devices for quickly delivering medication to the vascular system are readily apparent, there are, however, a number of disadvantages.
In using intravenous devices, for example, infection of the surrounding tissue (celulitis) and systemic infection (bacteremia) can sometimes occur. Further, clotting of the vein (thrombosis) and accidental injection of the medication outside of the vein--causing extensive tissue destruction--also occur with some regularity. Perhaps the greatest problem with such intravenous devices is simply the procedure involved in inserting such devices. Often, locating the vein in which such an intravenous device can be placed is difficult, subjecting the patient to a painful ordeal as the doctor or nurse probes the area under the skin in an attempt to find a vein. All of these problems are particularly magnified in those patients requiring long-term (e.g. greater than two weeks) administration of medication.
As an answer to the well known deficiencies of conventional intravenous devices, several systems have been developed for use as an alternative. One such device is the Hichman Broviac silastic catheter which is tunneled under the skin, usually in the chest, and inserted into a large vein, usually the subclavian vein. Other such systems include the Port-a-cath Infus-a-port (sold by Infasaid), and the Mediport (sold by Norfolk) which are essentially cavity structures which are implanted under the skin and have a self-sealing septum. Medication is injected through a needle inserted through the skin and septum into the cavity. A catheter leads from the cavity to the vein to deliver the medication to the vein.
While such implant devices are sometimes a desirable alternative to an intravenous device, a number of problems still exist. For example, infection and clotting in the vein and catheter are still major problems. Further, these implant devices require minor surgery for insertion, and are nevertheless difficult to implant in children. Further, the bulge caused by such implant devices are cosmetically unappealing.
Perhaps the greatest difficulty with such implant devices is that because of the many complications that can arise, many such implant devices must be prematurely removed from the patient. Thus, while such implant devices are often a desirable alternative to intravenous devices, in practice many problems exist with such implant devices.